Platform trucks are well known in industry for moving loads that cannot be easily transported by hand. A typical platform truck includes a generally rectangular, flat, material-supporting surface having two swivel casters positioned at the handle or rear end of the truck and two unidirectional, non-swiveling, wheels at the front end of the platform truck. This configuration is advantageous for carrying heavy loads because it prevents the front casters from following the terrain while allowing the operator to control the path of the swiveling casters with the handle. However, this configuration is difficult to maneuver in tight areas where loads are often transported due to the requirement that the rear of the platform truck be pivoted around the front wheels, placing the center of the turning radius in between the front unidirectional wheels. Thus, in these situations it is advantageous for the front casters to swivel along with the rear casters.
Thus, it has been suggested in the prior art to construct the platform truck so that the handle can be moved from one end of the platform truck to the other. In these platform trucks, a post receptacle is provided at each corner of the platform for receiving the ends of an inverted U-shaped handle. In this manner, when a user needs a rear steer platform truck, the handle can be placed at the rear of the platform truck near the swiveling casters; and if the user needs a front steer platform truck, the handle can be placed at the front of the platform truck near the unidirectional wheels. However, these constructions have proven to be cumbersome and unreliable as the handles commonly get bent or sprung and are difficult, if not impossible, to move from one end of the platform truck to the other.
It has also been suggested in the prior art to provide selectable swiveling casters on a platform truck which allow the front casters to swivel or lock in a unidirectional position. For example, some platform trucks provide a spring loaded pin mounted on each caster wheel that engages a notch thereon to prevent that front caster wheel from swiveling when it is desired to lock it in place. Unfortunately, to release the front casters the user has to physically pull a ring at each front caster wheel, requiring the user to step away from the handle, thereby releasing control of the load. Resetting the caster to a locked position is even more cumbersome for the user, requiring the user to orient the caster so that the pin can be re-engaged to the notch. Therefore, what is lacking in the art is a platform truck that includes a user-friendly means of locking and unlocking the caster wheels of the platform truck from the operating position of the platform truck.
Thus, the need exists for a platform truck having an actuator positioned conveniently at the handle end of the truck which allows the front casters to be switched between a fixed position and a swivel position to more easily negotiate tight turns and doorways. The platform truck should also include a more convenient construction for switching the handle from one end of the platform truck to the other, which eliminates the need to remove the handle from the platform truck. The handle should also be stowable in the platform truck itself for ease in loading and unloading the platform truck.